300 N. Washington St.
Suite B-100
Alexandria, VA 22314

GlobalSecurity.org In the News

Newsday (New York) July 08, 2003

Cause and Effect

Shuttle test yields gaping hole in wing

By Earl Lane

San Antonio - In a dramatic climax to the Columbia accident investigation, a chunk of foam fired at high speed blasted a gaping hole in a key space shuttle wing panel yesterday, a result an accident investigation board member called "the smoking gun."

Spectators and reporters about 50 yards away gasped and shouted as the foam projectile tore through a partial shuttle wing mock-up at the Southwest Research Institute here. The briefcase-sized piece of insulation foam opened a roughly square hole measuring about 16 inches on a side, according to G. Scott Hubbard, the accident board member overseeing the test.

With the test, Hubbard said, "I believe that we have found the smoking gun. I believe we have established that the foam block that fell off the external tank [on launch day] was, in fact, the most probable cause, the direct cause of the Columbia accident."

Hubbard said the hole is roughly the same magnitude as the breach that investigators believe brought down Columbia. Based on an analysis of recovered debris and sensor data from Columbia, investigators have calculated that a hole at least 10 inches in diameter had opened in the shuttle's left wing to allow sufficient super-hot gases to penetrate the craft during re-entry and cause its destruction.

Investigators have long suspected that a piece of foam insulation that struck Columbia about 80 seconds after launch could have caused the breach, but they have been trying to connect the dots with a series of foam impact tests on wing edge panels and fiberglass surrogates.

Investigators believe the fatal breach opened at or near leading edge panel No. 8 on Columbia. In yesterday's test, a 35-foot-long compressed gas cannon fired a box-shaped piece of insulation foam at the lower half of a No. 8 left wing panel taken from the shuttle Atlantis. The panel, made of a composite material called reinforced carbon-carbon, had been used on 27 shuttle missions, comparable to the use seen by the same panel on Columbia. The foam was fired at the same velocity, about 530 mph, and believed angle of impact as the chunk that hit Columbia.

Hubbard said he was surprised by the extent of damage, which he said provoked in him a stomach-wrenching reaction followed by, "Oh, my God." As a physicist, he said, he is gratified the testing allowed the board to show "in a much more direct way" what brought down Columbia. But he added, "I know that it was the source of tragedy, so that makes me feel very sad." All seven crew members perished.

Columbia's crew did not have the ability to inspect the underside of the wing in orbit, and Hubbard said a launch camera that photographed the craft during lift-off had a resolution just on the margin of being able to see a 16-inch hole. No evidence of such an opening was seen. Another camera that might have spotted the damage was out of focus.

The test raises new questions about NASA's decision not to ask the Pentagon to use its ground-based telescopes or spy satellites to photograph Columbia while in orbit. Hubbard declined to speculate on whether such assets would have seen a 16-inch hole in the shuttle's underside. He noted it might have been difficult if the hole was dark against a dark background. John Pike, a military analyst with the nonprofit GlobalSecurity.org, said that, depending on conditions, the hole "was in the ballpark of what a satellite would have seen."

The hole created yesterday was in stark contrast to the relatively small crack that appeared when foam was fired last month at wing edge panel No. 6 from Discovery. But yesterday's test was designed to slam an entire edge of the foam against panel 8. Hubbard also noted that the carbon panels can vary as much as 70 percent in their breaking strength.

Hubbard declined to speculate on whether yesterday's test result might prompt a delay in NASA's plans for resuming flights of the shuttles by early next year. He said the board already has recommended that the agency have the ability to inspect and repair the shuttle's heat-resistant skin in orbit. But experts have said it will be difficult to repair the carbon-carbon panels aloft, particularly if the damage is as severe as that produced yesterday. An alternative is to have a crew rescue capability with another shuttle if necessary.

GRAPHIC: AP Photo - A NASA investigator checks the damage caused in a wing panel in yesterday's test-firing of a chunk of foam.

Copyright 2003, Newsday, Inc.